<!DOCTYPE html>
<html lang="en">

<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>Document</title>
	<style>
		body {
			height: 3000px;
		}

		* {
			margin: 0;
			padding: 0;
		}

		.page-header {
			height: 200px;
			background-color: #ccc;
			line-height: 200px;
			text-align: center;
		}

		.title {
			background-color: blue;
			font-size: 40px;
			position: sticky;
			top: 0px;
		}

		h1 {
			background-color: skyblue;
		}
	</style>
</head>

<body>
	<div class="page-header">头部</div>
	<div class="content">
		<div class="item">
			<div class="title">A</div>
			<h1>A1</h1>
			<h1>A2</h1>
			<h1>A3</h1>
			<h1>A4</h1>
			<h1>A5</h1>
			<h1>A6</h1>
			<h1>A7</h1>
			<h1>A8</h1>
			<h1>A9</h1>
		</div>
		<div class="item">
			<div class="title">B</div>
			<h1>B1</h1>
			<h1>B2</h1>
			<h1>B3</h1>
			<h1>B4</h1>
			<h1>B5</h1>
			<h1>B6</h1>
			<h1>B7</h1>
			<h1>B8</h1>
			<h1>B9</h1>
		</div>
		<div class="item">
			<div class="title">C</div>
			<h1>C1</h1>
			<h1>C2</h1>
			<h1>C3</h1>
			<h1>C4</h1>
			<h1>C5</h1>
			<h1>C6</h1>
			<h1>C7</h1>
			<h1>C8</h1>
			<h1>C9</h1>
		</div>

	</div>
</body>

</html>